package cn.stylefeng.guns.modular.robot.utils;

import cn.stylefeng.guns.modular.robot.entity.dto.MailHistoryDto;
import cn.stylefeng.guns.modular.robot.entity.vo.req.ReceiveMailParam;
import lombok.SneakyThrows;
import org.apache.commons.io.IOUtils;
import org.apache.commons.lang3.StringUtils;
import org.springframework.util.CollectionUtils;

import javax.mail.*;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.mail.internet.MimeMultipart;
import javax.mail.internet.MimeUtility;
import java.io.*;
import java.nio.file.Files;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.ArrayList;
import java.util.List;
import java.util.UUID;

public class ParseMail {
    /**
     * 删除邮件
     *
     * @param messages 要解析的邮件列表
     */
    public static void deleteMessage(Message... messages) throws MessagingException, IOException {
        if (messages == null || messages.length < 1)
            throw new MessagingException("未找到要解析的邮件!");

        // 解析所有邮件
        for (int i = 0, count = messages.length; i < count; i++) {

            /**
             *   邮件删除
             */
            Message message = messages[i];
            String subject = message.getSubject();
            // set the DELETE flag to true
            message.setFlag(Flags.Flag.DELETED, true);
            System.out.println("Marked DELETE for message: " + subject);


        }
    }

    /**
     * 获得邮件主题
     *
     * @param msg 邮件内容
     * @return 解码后的邮件主题
     */
    public static String getSubject(MimeMessage msg) throws UnsupportedEncodingException, MessagingException {
        return MimeUtility.decodeText(msg.getSubject());
    }

    /**
     * 获得邮件发件人
     *
     * @param msg 邮件内容
     * @return 姓名 <Email地址>
     * @throws MessagingException
     * @throws UnsupportedEncodingException
     */
    public static String getFrom(MimeMessage msg) throws MessagingException, UnsupportedEncodingException {
        String from = "";
        Address[] froms = msg.getFrom();
        if (froms.length < 1)
            throw new MessagingException("没有发件人!");

        InternetAddress address = (InternetAddress) froms[0];
        String person = address.getPersonal();
        if (person != null) {
            person = MimeUtility.decodeText(person) + " ";
        } else {
            person = "";
        }
        from = person + "<" + address.getAddress() + ">";

        return from;
    }

    /**
     * 根据收件人类型，获取邮件收件人、抄送和密送地址。如果收件人类型为空，则获得所有的收件人
     * <p>Message.RecipientType.TO  收件人</p>
     * <p>Message.RecipientType.CC  抄送</p>
     * <p>Message.RecipientType.BCC 密送</p>
     *
     * @param msg  邮件内容
     * @param type 收件人类型
     * @return 收件人1 <邮件地址1>, 收件人2 <邮件地址2>, ...
     * @throws MessagingException
     */
    public static String getReceiveAddress(MimeMessage msg, Message.RecipientType type) throws MessagingException {
        StringBuffer receiveAddress = new StringBuffer();
        Address[] addresss = null;
        if (type == null) {
            addresss = msg.getAllRecipients();
        } else {
            addresss = msg.getRecipients(type);
        }

        if (addresss == null || addresss.length < 1)
            return null;
        for (Address address : addresss) {
            InternetAddress internetAddress = (InternetAddress) address;
            receiveAddress.append(internetAddress.toUnicodeString()).append(",");
        }

        receiveAddress.deleteCharAt(receiveAddress.length() - 1); //删除最后一个逗号

        return receiveAddress.toString();
    }

    /**
     * 判断邮件中是否包含附件
     *
     * @return 邮件中存在附件返回true，不存在返回false
     * @throws MessagingException
     * @throws IOException
     */
    public static boolean isContainAttachment(Part part) throws MessagingException, IOException {
        boolean flag = false;
        if (part.isMimeType("multipart/*")) {
            MimeMultipart multipart = (MimeMultipart) part.getContent();
            int partCount = multipart.getCount();
            for (int i = 0; i < partCount; i++) {
                BodyPart bodyPart = multipart.getBodyPart(i);
                String disp = bodyPart.getDisposition();
                if (disp != null && (disp.equalsIgnoreCase(Part.ATTACHMENT) || disp.equalsIgnoreCase(Part.INLINE))) {
                    flag = true;
                } else if (bodyPart.isMimeType("multipart/*")) {
                    flag = isContainAttachment(bodyPart);
                } else {
                    String contentType = bodyPart.getContentType();
                    if (contentType.contains("application")) {
                        flag = true;
                    }

                    if (contentType.contains("name")) {
                        flag = true;
                    }
                }

                if (flag) break;
            }
        } else if (part.isMimeType("message/rfc822")) {
            flag = isContainAttachment((Part) part.getContent());
        }
        return flag;
    }

    /**
     * 判断邮件是否已读
     *
     * @param msg 邮件内容
     * @return 如果邮件已读返回true, 否则返回false
     * @throws MessagingException
     */
    public static boolean isSeen(MimeMessage msg) throws MessagingException {
        return msg.getFlags().contains(Flags.Flag.SEEN);
    }

    /**
     * 判断邮件是否需要阅读回执
     *
     * @param msg 邮件内容
     * @return 需要回执返回true, 否则返回false
     * @throws MessagingException
     */
    public static boolean isReplySign(MimeMessage msg) throws MessagingException {
        boolean replySign = false;
        String[] headers = msg.getHeader("Disposition-Notification-To");
        if (headers != null)
            replySign = true;
        return replySign;
    }

    /**
     * 获得邮件的优先级
     *
     * @param msg 邮件内容
     * @return 1(High):紧急  3:普通(Normal)  5:低(Low)
     * @throws MessagingException
     */
    public static String getPriority(MimeMessage msg) throws MessagingException {
        String priority = "普通";
        String[] headers = msg.getHeader("X-Priority");
        if (headers != null) {
            String headerPriority = headers[0];
            if (headerPriority.contains("1") || headerPriority.contains("High"))
                priority = "紧急";
            else if (headerPriority.contains("5") || headerPriority.contains("Low"))
                priority = "低";
            else
                priority = "普通";
        }
        return priority;
    }


    public static String getTextMultipart(Part part) throws Exception {
        if (part.isMimeType("text/html")) {
            return (String) part.getContent();
        } else if (part.isMimeType("text/plain")) {
            return (String) part.getContent();
        }
        return "";
    }

    /**
     * 获得邮件文本内容
     *
     * @param part    邮件体
     * @param content 存储邮件文本内容的字符串
     * @throws MessagingException
     * @throws IOException
     */
    public static void getMailTextContent(Part part, StringBuffer content) throws MessagingException, IOException {
        // 如果是文本类型的附件，通过getContent方法可以取到文本内容，但这不是我们需要的结果，所以在这里要做判断
        boolean isContainTextAttach = part.getContentType().indexOf("name") > 0;
        if (part.isMimeType("text/*") && !isContainTextAttach) {
            content.append(part.getContent().toString());
        } else if (part.isMimeType("message/rfc822")) {
            getMailTextContent((Part) part.getContent(), content);
        } else if (part.isMimeType("multipart/*")) {
            Object mpart = part.getContent();
            if (mpart instanceof Multipart) {
                Multipart multipart = (Multipart) part.getContent();
                int partCount = multipart.getCount();
                for (int i = 0; i < partCount; i++) {
                    BodyPart bodyPart = multipart.getBodyPart(i);
                    getMailTextContent(bodyPart, content);
                }
            }
        }
    }

    /**
     * 保存附件
     *
     * @param part
     * @param receiveMailParam
     * @throws MessagingException
     * @throws IOException
     */
    public static List<MailHistoryDto.Attachment> saveAttachment(Part part, ReceiveMailParam receiveMailParam) throws MessagingException, IOException {
        List<MailHistoryDto.Attachment> attachments = new ArrayList<>();
        if (part.isMimeType("multipart/*")) {
            Multipart mp = (Multipart) part.getContent();
            BodyPart mPart;
            for (int i = 0; i < mp.getCount(); i++) {
                String fileName = null;
                MailHistoryDto.Attachment attachment = null;
                mPart = mp.getBodyPart(i);
                String disposition = mPart.getDisposition();
                if (Part.ATTACHMENT.equals(disposition) || Part.INLINE.equals(disposition)) {
                    fileName = mPart.getFileName();
                    if (null != fileName && fileName.toLowerCase().contains("gb")) {
                        fileName = MimeUtility.decodeText(fileName);
                    }
                    if (null != fileName && fileName.toLowerCase().contains("utf")) {
                        fileName = MimeUtility.decodeWord(fileName);
                    }
                    attachment = saveFile(fileName, mPart.getInputStream(), receiveMailParam);
                } else if (mPart.isMimeType("multipart/*")) {
                    List<MailHistoryDto.Attachment> multipartAttachments = saveAttachment(mPart, receiveMailParam);
                    if (!CollectionUtils.isEmpty(multipartAttachments)) {
                        attachments.addAll(multipartAttachments);
                    }
                    continue;
                } else {
                    fileName = mPart.getFileName();
                    if ((fileName != null) && (fileName.toLowerCase().contains("gb2312"))) {
                        fileName = MimeUtility.decodeText(fileName);
                        attachment = saveFile(fileName, mPart.getInputStream(), receiveMailParam);
                    }
                    if ((fileName != null) && (fileName.toLowerCase().contains("utf-8"))) {
                        fileName = MimeUtility.decodeWord(fileName);
                        attachment = saveFile(fileName, mPart.getInputStream(), receiveMailParam);
                    }
                }
                if (StringUtils.isBlank(fileName)) {
                    continue;
                }
                attachments.add(attachment);
            }
        } else if (part.isMimeType("message/rfc822")) {
            List<MailHistoryDto.Attachment> messageAttachments = saveAttachment((Part) part.getContent(), receiveMailParam);
            if (!CollectionUtils.isEmpty(messageAttachments)) {
                attachments.addAll(messageAttachments);
            }
        }
        return attachments;
    }

    @SneakyThrows
    private static MailHistoryDto.Attachment saveFile(String fileName, InputStream inputStream, ReceiveMailParam receiveMailParam) {
        Path path = Paths.get(receiveMailParam.getMailSetting().getAttachmentPath(), UUID.randomUUID().toString().replace("-", ""));
        try (BufferedOutputStream bos = new BufferedOutputStream(Files.newOutputStream(path))) {
            IOUtils.copy(inputStream, bos);
            MailHistoryDto.Attachment attachment = new MailHistoryDto.Attachment();
            attachment.setFileName(fileName);
            attachment.setPath(path);
            return attachment;
        } catch (Exception e) {
            return null;
        } finally {
            if (inputStream != null) {
                inputStream.close();
            }
        }
    }
}
